The knee joint connects the upper leg bone (femur) to the larger lower leg bone (tibia). The bone ends are covered in a layer of smooth cartilage, allowing the joint to easily bend or straighten. In osteoarthritis, the cartilage becomes thin and irregular. With ongoing osteoarthritis, bone growth on the edges of the knee joint (osteophytes) changes the knee’s appearance, enlarging the joint profile.
Symptoms from osteoarthritis may vary and range in intensity. Pain and stiffness characterize the onset of knee osteoarthritis and as the arthritis progresses, symptoms increase, especially with prolonged activities such as standing, climbing stairs, or carrying heavy loads. As the osteoarthritis progresses, bending and straightening the knee may become limited.
Image 1: Knee osteoarthritis